From your favorite restaurant to the local gas station, there are potential predators everywhere, devising ways to get their hands on your money. But what happens when we catch them red-handed? Tomorrow night on "Nightline" prime, we're turning the tables and showing you how to protect yourself. I just thought that maybe I had been blessed. It can take one phone call. The prize that you're receiving, ma'am, is $1.2 million. I truly, truly was convinced. Reporter: It could happen in your living room. They became my friends. They robbed you. Reporter: Or even in your church. How many of you want to get paid this morning? Raise your hand. This is your retirement? Yes. It's gone. Yes. It's gone. Reporter: People anxious to get their hands on your money are everywhere. And now, as millions of summer travelers hit the road, beware. A new kind of thief could be stealing your hard-earned money. I knew it was stealing. I knew it was wrong. Reporter: You're witnessing a new breed of credit card thief caught on tape. This drive through attendant in Florida is wiping each card twice. Once to charge for the food and again through something called a skimmer, which steals the card number, expiration date and information. Richard Norris was the card's owner. You watch them use your card. I never paid attention to a skimmer being so small. Reporter: But for Norris, the worst part wasn't the money. It was the deception. I think that's what makes it worse. He actually made a point to, how are you doing? Good afternoon. Good morning, whatever the case would be. Always seemed to be smiling. He was making more than minimum wage. Reporter: Credit card skimming is becoming a national problem. Just ask Jeffrey marshal of the Nassau county police department in New York. A waitress in here was doing just that. Yep. Reporter: How many cards did she get? 20, 25 cards. Reporter: Who is the person doing this one? A male individual. Reporter: A two-minute drive from your station, you've seen three different scores with scams? Yes. It can happen anywhere. Reporter: Now, electronic skimmers are so advanced they don't need a human to operate. Check out this crook modifying an atm in an convenient store. He places a card slot that contains a skimmer, over the real one. Will check it to make sure the card works. Reporter: Two occasions he walks up to that atm, puts on two devices. You'd never know. That's correct. Reporter: To protect yourself, check your account, a lot. Once you report loss or theft, the law says you have no additional responsibility for charges you didn't make. Tomorrow night, "Nightline prime" is on the case, bringing you an hour, called "Catch me if you can," with more on the shocking summer scams. Tune in 10:00 P.M. Eastern right here on ABC.

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